(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a young female who presented at her local hospital with 2 weeks of fatigue, fever, abdominal pain, nausea, vomiting and jaundice. Blood workup at that time was positive for IgM anti-HAV and a diagnosis of acute hepatitis A was established. She presents 3 months later with persistent jaundice, nausea, vomiting and elevated liver enzymes (AST 956, ALT 455, alkaline phosphatase 88, total bilirubin 16.5). Other relevant labs showed: INR 2.4, positive anti-smooth muscle antibodies (ASMA), elevated IgG level of 2530 and negative serologies for HBV and HCV, anti-nuclear (ANA) and anti-mitochondrial-M2 antibodies (AMA-M2). A liver biopsy is performed.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A twelve month old girl was admitted to the hospital with an ill-defined subcutaneous mass in the left parietal region. When she was 4 months, the mother noticed a small swelling on the left side of the head, just above the ear. It enlarged quickly until it reached a disfiguring size. Outside radiological studies revealed a tumor arising in the left parietal bone. She underwent excision of the mass and reconstruction of skull defect with bone graft. The child was well until 8 months of age, when skin ulcers and multiple masses developed in the vicinity of previous excision, complicated by CSF leak and infection of bone graft. She was referred to KFSH&RC for further management. On admission, she was febrile and lethargic but alert. There were multiple, firm and tender skull masses in left temporo-parietal area, the biggest of which measured 6 x 7 x 4 cm, and an ulcer measuring 2 x 3 cm in the left supra-auricular area over the exposed bone flap.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 38-year-old Caucasian male was diagnosed with biopsy-proven essential proliferative IgA nephropathy and renal arteriosclerosis in 2007. He developed hypertension, end-stage renal disease, and was on hemodialysis three days a week. His blood pressure had been recorded between 101-149 mmHg systolic and 60-88 mmHg diastolic.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A Caucasian woman in her early 40s without significant past medical and family history was found to be thrombocytopenic during the third trimester of her pregnancy. Her platelet count was 24x109/L. She received platelets transfusion and underwent an emergent Cesarean section delivery without complication. Her postpartum course was complicated by a mild hemolytic anemia and she underwent plasmapheresis with no response. She was tapered off of steroids and maintained a platelet count of 45x10^9/L. One year later the patient presented with acute dull pain in right upper abdominal quadrant and enlarged liver. Her LDH was 694 IU/L (<170) and a CT scan of the abdomen revealed hepatosplenomegaly with hepatic (Budd-Chiari syndrome) and splenic veins thromboses.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 42 year old female presented with transient new onset dizziness. She had a past history of a right posterior cerebral artery aneurysm in 1989 which was clipped and she had a residual left homonymous hemianopia. On examination at the time of her first presentation there were no additional findings. One year later she described intermittent headache, vertigo, difficulty speaking and her family noticed she occasionally used the wrong word. Now on examination she had mild dysarthria and a wide based ataxic gait. Plantars were down-going. There was no sensory abnormality and Romberg's test was negative.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 7 year old boy originally presented with a cerebellar lesion. The MRI demonstrated a complex posterior fossa mass with predominantly T1 darkness and a nidus of enhancement (Fig 1). The mass was impinging upon the posterior aspect of the fourth ventricle. This original resection was followed by a second resection approximately 2 years later and a third resection approximately 4 years after the first resection.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The teenager living in a group home with history of severe behavior problems including acting out and hair pulling has a neurology consult due to possible seizures. The measured Intelligence Quotient was approximately 40. No identification of father was possible and the mother was unavailable due to diagnosis of paranoid schizophrenia and placement in another group home.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a thirteen year-old female with a history of asthma who presented to the emergency department with a three-week history of an enlarging right neck mass. When the mass was first noticed, it was small and felt to be lymphadenopathy. In the subsequent weeks, it rapidly enlarged and became more painful. She had no fever and no signs or symptoms of upper respiratory tract infection. There was no respiratory compromise or dysphagia. She reported no recent weight loss. Physical examination showed her to be afebrile with normal vital signs. There was a 4 x 3 cm mildly tender, firm mass at the anterior border of the right sternocleidomastoid muscle at the level of the hyoid bone. No stridor was appreciated.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient was a male in his seventies with a history of non insulin-dependent diabetes mellitus and hyperlipidemia. He developed hypertension at the age of his early fifties and was subsequently diagnosed with polycystic kidney disease. The patient's renal function progressively declined and he underwent cadaveric renal transplantation at the age of sixties. Immunosuppressive regimen included cyclosporine, azathioprine, and prednisone. Eight years post-transplant, the patient was diagnosed with squamous cell carcinoma in-situ of the skin of the right and left shoulders and overlying the trapezius muscle. Over the next two years, numerous squamous cell carcinomas developed on the patient's head and neck, upper extremities, chest, and back. Ten years post-transplant, the patient developed a nodular mass on his right forearm. Excision of this mass was performed and it was submitted for gross and microscopic examination. Hematoxylin and eosin stained slides and immunohistochemical stains

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A previously healthy 2-year-old child first presented with a new limp and mild weakness of her right leg. Initial workup with x-rays was negative. Her condition worsened over two weeks with new neurological deficits including worsening gait changes resulting in crawling rather than walking and holding her right arm in a flexed position. MRI (T1 with contrast) showed a large solid and cystic intra-axial mass with markedly heterogeneous enhancement centered within the frontoparietal region with extension into and expansion of the body of the corpus callosum (Figures 1 and 2). Stereotactic biopsy for diagnosis and surgical decompression was performed. She was treated with steroids and anticonvulsants. Further chemotherapeutic treatment was scheduled, but she continued to worsen with lethargy and hypertonicity requiring hospitalization. She clinically deteriorated with unreactive pupils and cerebral posturing. MRI showed tumor progression with herniation. She expired three months after onset of her symptoms. A brain only autopsy was performed.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a two-year-old male who presented for orchidopexy of the right undescended testis. The parents stated that the right testis may have been present in the scrotum on past well-child visits, but is not present on the most recent exam. The past medical history is noncontributory and the review of systems is negative. Physical exam reveals a left testis that is normal to palpation and present in the scrotum. The patient was schedule for surgery with exam under anesthesia to assess whether the right testis is palpable in the scrotum, with the plan of performing an orchidopexy if an undescended testis is present or an orchiectomy if a hypoplastic testis or a testicular nubbin is present.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her 20s presented to her primary care physician with a complaint of abdominal discomfort and distension for approximately one month. The patient reported constipation but denied nausea, vomiting, sharp abdominal pain, and rectal bleeding. Physical examination demonstrated diffuse abdominal tenderness and firmness without guarding. A transvaginal ultrasound revealed a large, complex, cystic and solid soft tissue mass within the pelvis, extending to 2 cm above the umbilicus. A CT scan of the abdomen and pelvis showed involvement of the right adnexa. The patient underwent a right salpingo-oophorectomy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her 20s presented with a one-year history of bifrontal headaches that had recently worsened. After admission to the hospital, the patient displayed no other symptoms and no acute worsening of the headaches.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her late thirties who is 15 weeks pregnant (G1P0) visits the allergy and immunology clinic. She has a history of positive anti-thyroid antibody (subtype unkown) which was diagnosed ten years prior and is treated with Synthroid. She complains of urticaria, flushing, and cramping abdominal pain with exercise. These symptoms can also be evoked by hot showers and urticaria occasionally develop in areas of skin exposed to pressure or friction. The symptoms began occurring occasionally twenty years ago and have been progressively increasing in frequency and severity. The symptoms are generally well controlled by daily doses of fexofenadine and ranitidine taken thirty minutes prior to exercising. The patient also states that she experiences at least two mild headaches per week. She is concerned about the safety of her current medication regimen given her pregnancy. The physical exam is non-contributory. Laboratory studies are included in Table 1.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her 40s presented with a 7-year-history of muscle pain and weakness. She also complained of visual disturbances over the last five years that resulted in diplopia over the last year. Past medical and family histories were unremarkable. Neuro-ophthalmologic examination revealed left sixth nerve palsy. No other neurological abnormality was found. Laboratory investigation disclosed hypophosphatemia (12.3mg/L - normal, 27 to 45mg/L), phosphaturia, elevated serum alkaline phosphatase activity (345 IU/L - normal, 39 to 117 IU/L), and normal serum calcium levels (4.87mEq/L - normal, 4.20 to 5.40 mEq/L). No other clinical or metabolic abnormalities were detected. Computed tomographic scans showed a mass with lobulated borders arising on the meningeal surface of the cavernous sinus, measuring 3x2x2 cm (Figure 1). The radiological appearance was suggestive of cavernous-sinus meningioma. At surgical removal, a highly vascularized tumor was observed; owing to the proximity of the carotid artery and to the remarkable vascularization of the tumor, a complete resection was not possible. No radiotherapy or chemotherapy was carried out. Two weeks after the surgery, the patient had no complaints regarding muscle pain or weakness. Laboratory work-up showed marked improvement of serum calcium and alkaline phosphatase levels (4.49mEq/L and 192UI/L, respectively), and consistent increase in phosphate blood levels (16.6mg/L). The patient has been followed for the last four years with a marked improvement in her metabolic status (only with a mild hypophosphatemic metabolic state), and without any complaint of symptoms recurrence.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a woman in her mid-40s who presented to her primary care physician complaining of menorrhagia. In addition to uterine leiomyomas, radiologic work-up revealed a right complex ovarian cystic lesion, measuring approximately 4.5 cm in greatest dimension. The patient had no personal or family history of breast or ovarian cancer. She subsequently underwent a total abdominal hysterectomy and bilateral salpingooopherectomies.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her 40s presented with diffuse abdominal pain, meteorism and intermittent diarrhea. Gastrointestinal workup including abdominal computed tomography (CT) and magnetic resonance imaging (MRI) scans revealed a focal rounded lesion in segment IV of the liver without any edema or reactive changes. Although there was no history of progesterone or estrogen therapy, the radiographic appearance was considered to be suggestive of adenoma (Figure 1, arrow). The lesion was monitored by ultrasound after 3 years when a resection of hepatic segment VI was performed because of the presumed risk of a malignant transformation.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her 40s presented to the GI clinic with a seven-month history of intermittent, crampy abdominal pain. The pain was associated with diarrhea alternating with constipation, vomiting and a poor appetite, leading to an overall 50-pound weight loss. Past medical history was notable for a positive PPD, hypothyroidism and tonsillectomy. She was gravida 0 para 0 and was under treatment with Isoniazid for 6 months. Date of last menstrual period was not known. Physical examination showed an enlarged thyroid and stasis changes in lower extremities. No abdominal masses were noted. Rectal examination was declined. Gynecologic examination was not performed.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her mid 40s who presented with left flank pain and symptoms of ureteral obstruction. She was initially treated with antibiotics for urosepsis and subsequently underwent radiologic imaging that showed a large retroperitoneal mass.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A woman in her mid-50s presented with a slowly growing left lower lobe lung mass that measured up to 1.5 cm by CT scan. CT-guided FNA smears and cell block preparation were performed. The microscopic images of Diff-Quik stained direct smears and an H&E stained cell block section are shown in figures 1, 2 and 3.